Protect yourself from credit card fraud

NEW YORK (CNNMoney) -- In early March, hackers stole roughly 1.5 million credit card numbers from payment processor Global Payments, a company that processes card transactions for companies like Visa and MasterCard.

Fortunately, the thieves only swiped card numbers and not cardholders' names, addresses or Social Security numbers.

If hackers ever steal your information, here's what you can do to protect your accounts, according to Lynnette Khalfani-Cox, a personal finance expert and author of "Perfect Credit."

Contact the credit reporting agencies. Experian, Equifax and TransUnion can put a fraud alert on your credit report so no one else can open other accounts in your name.

File a police report. It's a key document that serves as proof if, say, your wallet was stolen with credit cards or Social Security numbers inside.

Consider signing up for a credit monitoring service. Often, a company whose security has been breached will offer credit monitoring to affected cardholders for free. They will actively monitor your credit reports with the three major bureaus for a period of time after your information has been stolen. You will be alerted if anything suspicious comes up, like changes made to your account information, credit inquiries, or a new account opened in your name.

For online purchases, try a single-use or 'virtual' credit card. This option, offered by banks like Citibank, Discover and Bank of America, offers a different number than your main credit card. That way, if hackers steal your account information from the retailer, they don't have the number for your main credit card. You can also set a limit for how much can be charged against the virtual card.